Finally, right click over the chart and click Re-Visualize. Then click Table. Scroll down and you'll see a table cell with a small, red triangle in the top-right corner. This corresponds to the note that was added to the bar chart. Hover over the red triangle to see the details of the note.

The note appearing beside the data point is updated to show the reply text. Hover over this text to see the Note window which shows all of the notes and replies. The most recent ones appear first in the window.